Design of tracking servo control system for holographic data storage

Holographic data storage is a strong candidate for the next generation archive storage device. However, disturbances such as external shock, vibration, flutter and eccentricity of the disk affects the holographic data storage device. Thus, tracking servo control is necessary in order to enhance the signal noise ratio and reduce the bit error rate and retrieve the data accurately. It is also inevitable to face track overlapping problem if there is no datum to apply servo control during the recording process. In this research, we suggest a method forming a holographic servo track to detect the tracking error signal continuously without using any additional laser diode or pre-format layer. The tracking servo controller is designed to improve the track following performance, and the validity of the proposed method is confirmed through experiments on our holographic data storage system.